The following descriptions and examples do not constitute an admission as prior art {XE “Unintended admission: prior art”} by virtue of their inclusion within this section.
Seismic exploration involves surveying subterranean geological formations for hydrocarbon deposits. A seismic survey may involve deploying seismic source(s) and seismic sensors at predetermined locations. The sources generate seismic waves, which propagate into the geological formations creating pressure changes and vibrations along their way. Changes in elastic properties of the geological formation scatter the seismic waves, changing their direction of propagation and other properties. Part of the energy emitted by the sources reaches the seismic sensors. Some seismic sensors are sensitive to pressure changes (hydrophones), while others to particle motion (e.g., geophones). Industrial surveys may deploy one type of sensors or both. In response to the detected seismic events, the sensors generate electrical signals to produce seismic data. Analysis of the seismic data can then indicate the presence or absence of probable locations of hydrocarbon deposits.
Some surveys include long streamers (e.g., as long as 8 kilometers or more), and may have eight or more streamers towed adjacent to one another. The vessels that tow these streamers are generally large and 100 foot long or more. Given the dimensional draft of these vessels, spread may be an issue. Also, the proposition of entanglement or other negative interaction with obstacles may be problematic.